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go fast... use some speed tape ;)

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I recently ran my first SARL race... great fun, come on out and play!

For the first race I decided to run pretty much exactly as I would normally... no speed tape or special fittings, etc. to get a baseline. I compromised a bit on this since my tanks were not full and I removed most all of my baggage for the race. I did leave my Oxygen bottle but pulled my flight bag which included tools. Okay idea at the time, but after Brian had to divert for a precautionary landing with engine trouble and ended up having to scrounge around for and hour to get a screwdriver and plier just to remove his cowling, I have decided to include my flight bag and tools as mandatory cross country race gear ;)

Several racers had gap tape of various kinds here and there... beyond looking the part of real racer I figured that it must actually work so I decided to give it a try.

I had a roll of Bowlus Maxi Gap Seal Tape (http://www.cumulus-soaring.com/bowlus.htm) that the glider guys use sitting around the hangar on the shelf that I had once used to cover up some tip cracking on my Cessna... finally I have a chance to use it as intended!

The tape is very thin and goes on and comes off especially easily. For my first test run I taped up my tips, the wingtip lens, the fuel caps, the tie-down holes, the seams of the wheel pants, and one of the air vents.

img1825in.jpg


img1826cn.jpg


Results... a clear increase in top end speed in excess of 2 mph... perhaps as high as 4 but I will need to repeat the run at a couple of different altitudes to stand by the higher value...

Others have used gaffers tape and I hope to give that a try too.

Other experiences?

Best places to tape up?

A plug for the upcoming AirVenture Cup from Mitchell, SD to Oshkosh... this one way run looks to be a very well organized event that includes lots of support including all of the local transportation, a breakfast, lunch, and dinner the day before the race, a breakfast on the morning of the race, a lunch at the finish provided by the local EAA chapter, a big dinner banquet at Oshkosh, and a weekly wrist pass to the big show, along with the usual SWAG ;)

Consider joining the AVC run when making your plans to Oshkosh this year!
 
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Air Venture Cup

I highly recommend the AVC race. If you are anywhere close to MHE, flying the race is a great way to get to OSH. The pre race atmosphere at MHE is fantastic, the race is exciting, and if I had the time off I would definitly be in the race. I haven't seen any RV reds on the entry list yet.

Chris M RACE 34
 
I use Gaffers Tape just because I have it

I had to satisfy a minimum order requirement When I bought some a few years ago for some task. It is thick, it leaves a residue that needs to be cleaned off with mineral spirits or other solvent, it does not come off easy when you try to get it off but it will partially come off in a 200+ mph wind and I have not measured any speed gain from using it. I think what you tested must be fantastic - don't waste you time on gaffers tape.

I have entered the AirVenture Cup Race.

Bob Axsom
 
Stephen,

First, its fun to watch the addiction set in...welcome to racing! :D

I also feel I measure a 2-3 knot gain with tape...I've measured it a few times in before and after tests. (Hey Bob, I think the gaffer's tape may be too thick...perhaps. We need to do a taping comparison/training day together sometime...so I can steal other good ideas from ya! ;))

My fave is 3M 471 tape, 2" wide. Best price so far is Amazon. Lots of colors, including red Stephen. Red is among the cheapest, white among the most expensive (not sure why). This stuff molds and shapes to curves easily, and has enough stretch to conform well. Better if ya put it on in a warm environment (cold makes it a bit brittle when applying. Good adhesion (if the surface is clean), with not much residue left afterwards (and I leave mine on for pretty long periods. One exception is the clear version. I don't recommend clear, as it yellows very fast, and becomes harder to remove, leaving more residue than the rest. Perhaps its the sun getting through the clear...not sure, but it just doesn't work as well as the colored varieties.

Where? Pretty much anywhere there's a seam. Access panels, tips, cowl halves, cowl aft edge, fairings (tail, gear leg), oil door, gas caps, fuel drains...the list goes on (I've been accused of being a bit obsessive with tape...once removed it all at once, and had a ball of it sized between a volleyball and a basketball!) Oh, don't forget the openings around the elevator and rudder hinges. But don't buy the expensive mylar from wings and wheels (sorry)...Jason Rovey discovered that Smart Water bottles (the brand) has different sizes that are perfect for the radius of those openings. I copied him...cut to fit, tape to hold (with more 471).

I also highly recommend AVC. Mitchell was great 2 years ago...very festive environment. Great mix of SARL, Reno Sport Class, Spruce Creek and other folks...very fun! I have a conflicting assignment this year pre-OSH with Falcon and the boys, or I'd be back...next MHE-OSH AVC for sure!

Its a disease...hello, my name is Bob...

Cheers,
Bob
Race 43
 
I can attest to Bob's affinity for tape. It would not be hard to convince the uninitiated that his plane was actually held together with the stuff.
 
Hi my name is Bob and I'm an Air Racer

I like that. Excuse me while I check out Amazon's stock of dark blue 3M 471. I had a very informative conversation with Red Hamilton at Ephrata before the GNAR III. He has me thinking in the direction of more power.

Bob Axsom
 
I like that. Excuse me while I check out Amazon's stock of dark blue 3M 471. I had a very informative conversation with Red Hamilton at Ephrata before the GNAR III. He has me thinking in the direction of more power.

Bob Axsom

Thinking?...10 more minutes waiting for your Cod lunch special and you guys would have started ordering parts and tearing down your motor.:D:D:D
 
Tape prices

With Nasty's recommendation, I thought I'd check out Amazon's selection of 3M tapes. I mean, if they had some GRAY tape, I just might give the AVC a try.

First off, you guys can relax. They don't have gray of any variety, so I won't be racing. :)

However, I did have to wonder how Amazon does their pricing. A 36-yard roll of black 1/2" 471 tape runs $13.71. However, a 36-yard roll of black 3/4" tape is $817.91! Must be what Bob Axom uses so much of and the price reflects the demand. :D

You guys have fun racing. I'll just keep putzing along ...
 
Bowlus tape is used by many glider pilots who assemble (and install and remove tape) every weekend. Fairly low residue, slightly stretchy, durable.

TODR
 
On my glider I use tape similar to Bowlus for the wings and stabilizer, i.e. parts that are rigged/derigged every day. For the leading edge of mylar tape seals we use Tesa 4104. It can't be streched like the Bowlus tape, but it is only half as thick and can stay on the plane for years without leaving residue. If you buy it from glider places like Wings And Wheels, you'll get white tape. But in fact it's available in various colors, even transparent.
 
I bought one roll of Black 3M 471 tape from Amazon

It must have been the next to last roll - it cost $50. I plan to try it at Three Forks - Big Sky Air Race. I will not buy that last roll at $817. I will keep the others in mind - Thanks!

Bob Axsom
 
I can attest to Bob's affinity for tape. It would not be hard to convince the uninitiated that his plane was actually held together with the stuff.

What...it's not?!?! ;)

I like that. Excuse me while I check out Amazon's stock of dark blue 3M 471. I had a very informative conversation with Red Hamilton at Ephrata before the GNAR III. He has me thinking in the direction of more power.

Bob Axsom

Now yer talkin'! Red's onto somethin' there...don't stop the drag reduction, but don't forget what Enzo Ferarri said either! (Quiz: inset quote here:____________________________________________________)

Thinking?...10 more minutes waiting for your Cod lunch special and you guys would have started ordering parts and tearing down your motor.:D:D:D

Big chuckle...wish I was there...we'd have been on the phone or the ipad ordering! :p

With Nasty's recommendation, I thought I'd check out Amazon's selection of 3M tapes. I mean, if they had some GRAY tape, I just might give the AVC a try.

First off, you guys can relax. They don't have gray of any variety, so I won't be racing. :)

However, I did have to wonder how Amazon does their pricing. A 36-yard roll of black 1/2" 471 tape runs $13.71. However, a 36-yard roll of black 3/4" tape is $817.91! Must be what Bob Axom uses so much of and the price reflects the demand. :D

You guys have fun racing. I'll just keep putzing along ...

A. Putzing...yeah right...remember, I've flown your 8, and its magnificent! You really oughta think about doing AVC Don. The schtick at Mitchell is really fun. Part race, part airshow, part Young Eagles, part family fun, etc. Just a great time! As for the tape, white 471 is pricey, but would be fine on your mo-chine. Tom Martin uses white on his gray camo Rocket, and it looks good.

(Oh and psssssst...pretty sure $871 was for a case of 20...or more...rolls. Look closely as you scroll through those Amazon listings...seems they have no order to how they pop up. Colors are all mixed up, quantities change from item to item. Be careful what you click on to order. However, if you buy a case box in error, I'll buy some from ya...if its the right color! :p)

Mark Frederick has some gray stuff...though not sure what it is. Mark?

Bowlus tape is used by many glider pilots who assemble (and install and remove tape) every weekend. Fairly low residue, slightly stretchy, durable.

TODR

On my glider I use tape similar to Bowlus for the wings and stabilizer, i.e. parts that are rigged/derigged every day. For the leading edge of mylar tape seals we use Tesa 4104. It can't be streched like the Bowlus tape, but it is only half as thick and can stay on the plane for years without leaving residue. If you buy it from glider places like Wings And Wheels, you'll get white tape. But in fact it's available in various colors, even transparent.

Can you guys expand on the Bowlus, and perhaps point us in a direction the colored varieties might be available. I bought some mylar gap seals from W&W a few years ago and did some testing. The system included some 1" wide white tape that was slightly stretchy. It went above the mylar strips. Is that the bowlus tape? Willing to try alternatives...always researching. Colors would be nice to find too! :)

FWIW, couldn't keep the mylar system on the rudder or upper elevator...zipped right off above about 180 kts. Lower elevator stayed on, but I abandoned the effort and went with sealing just the hingepoint access holes on the rudder and elevator (with Jason Rovey's Smart Water bottle pieces and 471 tape).

Overall, it seems 1" tape works well for flat seams, like cowling halves, wingtips, light lenses, etc. 2" seems to work better on gear leg fairings, tail fairings or anywhere that has compound curves or are not flat (flush). But that is personal pref or just technique...really "more of a guideline that a rule"! ;)

Cheers,
Bob
 
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Power is a wall that I have to get past carefully

Yes I know the Ferrari quote about aerodynamics and power and unfortunately I belong in the "don't know" group. I trust and respect Red Hamilton and that is why I was so engrossed in the conversation with him at Ephrata before the Great Northwest Air Race III. He consistently beats everyone in his class and theoretically more powerful classes whether he flies his oldest Cessna 180 still in service or his Wittman W-10 Tailwind. I am fairly fast but he beats my by 20-30 mph with a 40 cu. in. smaller displacement engine. I can repeat the names Ly-con and Barrett, etc. as well as the next bumpkin but the pure knowledge is simply not there. I need that personally. Buying and bolting on is simply a change of state with no penetration into knowledge of the difference. I like the feeling that striving for optimum performance is a process and to make the right decisions I need to be an intellectual part of it. The money involved is outrageous and I feel many claims and promises are without merit. In that environment "trust and Respect" are precious.

Bob Axsom
 
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The Bowlus type tape is fairly stretchy, so it's easy to get around corners, but it does come off when you stretch it too much, it might split, it's certainly not permanent. But for things like taping the wing-fuselage transition on a glider it's perfect. Think vinyl electrical tape.

The mylar tape on my control surfaces is held in place with double sided tape, and then the Tesa 4104 is put over the leading edge of the mylar to make that transition smoother. The Tesa is not supposed to hold the mylar in place. Again, my only experience is with gliders, and the vne in mine is 100 kts (low for a modern glider, but my glider is older than I am ...), so I can't comment on 180 kts performance. But I've only seen the mylar tapes come off when they were a few years old. I also suspect the Tesa 4104 alone will stay on at 180 kts, since it has good adhesion and is very thin (< 3 thou).

BTW, I've had 4104 strips along the leading edge of my wings for ~60 hours now, and they show no signs of weakness yet.
 
Can you guys expand on the Bowlus, and perhaps point us in a direction the colored varieties might be available. I bought some mylar gap seals from W&W a few years ago and did some testing. The system included some 1" wide white tape that was slightly stretchy. It went above the mylar strips. Is that the bowlus tape? Willing to try alternatives...always researching. Colors would be nice to find too! :)
Sounds like it. White only IIRC, slightly stretchy, and W&W would certainly carry it. I think you can get 2" as well. As others have said, it's not "permanent", but it seems to last 2 years on my CT (wings have to come off every other annual) where I use it for wing root taping.

TODR
 
The Bowlus type tape is fairly stretchy, so it's easy to get around corners, but it does come off when you stretch it too much, it might split, it's certainly not permanent. But for things like taping the wing-fuselage transition on a glider it's perfect. Think vinyl electrical tape.

The mylar tape on my control surfaces is held in place with double sided tape, and then the Tesa 4104 is put over the leading edge of the mylar to make that transition smoother. The Tesa is not supposed to hold the mylar in place. Again, my only experience is with gliders, and the vne in mine is 100 kts (low for a modern glider, but my glider is older than I am ...), so I can't comment on 180 kts performance. But I've only seen the mylar tapes come off when they were a few years old. I also suspect the Tesa 4104 alone will stay on at 180 kts, since it has good adhesion and is very thin (< 3 thou).

BTW, I've had 4104 strips along the leading edge of my wings for ~60 hours now, and they show no signs of weakness yet.

Sounds like it. White only IIRC, slightly stretchy, and W&W would certainly carry it. I think you can get 2" as well. As others have said, it's not "permanent", but it seems to last 2 years on my CT (wings have to come off every other annual) where I use it for wing root taping.

TODR

Thanks guys. Spent some more time ont he W&W site refreshing my memory, and when I tested the mylar system, I did use the gray teflon tape underneath (for rub resistance), the double-sided tape under the mylar leading edge, and the white TESA tape over the leading edge, as a smoother/sealer. It is very high quality stuff.

I first ran into trouble with the rudder seal, beacuse it didn't fit or seal well at the the area where the tail fairing closes the gap between the VS (above the HS) and the aft fuselage below the HS (on my plane, those two inspection panels just under the HS and Elevator). I figured it just separated there, and peeled off...and my chase confirmed it on the second test (I'm a slow learner...had to try it twi$e!) :rolleyes:

The upper elevator-to-HS gap also peeled away, though at a higher speed than the rudder. Only the lower elevator-to-HS mylar gap seal stayed put.

I did everything per instructions...except...I did not use the inner sealing tape (the one inside the gap area itself). Perhaps that's part of what caused the failure. Here's a pic, credit to the Wings and Wheels site:

wing%252520seals.jpg


I decided to just seal the openings at the elevator and rudder hinge, though I did note that Mark Frederick used the leftover W&W mylar that I gave him to span just across those elevator openings...hmmmm.

On the W&W site, I see no mention of Bowlus, but they do have a couple new products...the USA Vinyl tape (which sounds like 471 but is much cheaper) and the W&W White Poly tape. Both only in white, as you said. Might try a roll of that USA Vinyl just to compare it to 471.

Also interested in the turbulator tape. I see some fast glass planes with it at Reno, installed in strategic locations.

Fun to experiment, but I think Stephen's original post in on the mark...tape does make a difference!

Cheers,
Bob
 
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Pardon me for butting in, but I understand that on RV's and Rockets it's not wise to seal the ailerons. As I understand it, an open aileron gap is necessary for proper control surface airflow and proper functioning---correct?


Lee...
 
Pardon me for butting in, but I understand that on RV's and Rockets it's not wise to seal the ailerons. As I understand it, an open aileron gap is necessary for proper control surface airflow and proper functioning---correct?


Lee...

Lee,

You're not butting in at all...and you make a great point. I've been told the same thing, and have never sealed the ailerons for that very reason. I have no evidence other than the stories of those that tried it, and found the aircraft very hard to control.

The picture above (of the W&W taping system) looks like a generic control surface, so one might think it could work for an RV aileron...but Lee's right...conventional wisdom and field experience (from word of mouth) says don't tape the aileron gaps.

I do have aileron hinge bolt fairings, but those don't fill any of the gap between the wing and the ailerons. Not sure I can measure a difference in speed with those...figure it's one of those small incremental bits of speed (that's the hope anyway!) :)

Cheers,
Bob
 
Stephen taped up his Beautiful RV-7 last night. (not the ailerons) and flew it to a RV gold 1st place today 223.4mph in the Big Sky Air Race. Then flew home to seattle in <3hrs....... Nice Job Stephen!
 
TAPE

I think tape makes me go faster, but at BSAR the rain shower really tore it up. There was lots of shreds hanging out in the wind when I finished.

BTW I think Stephen needs more stuff taped.
 
Black 3M 471 tape results at BSAR II on Race #71

A cursory look at the black tape after the race at Three Forks, Montana on 7-7-12 showed it all still in place which seemed to be an improvement over the Gaffers tape used previously. Now I'm not so sure. I took these photos yesterday evening after returning from Montana to my home in Arkansas and flying one speed test on a cooling air outlet mod:

Upper end of nose gear strut to cowl:
IMG_6133.jpg

The lower cowl is known to pressurize and blow out the gear leg penetration this is just another test that shows the pressure is too high for tape to handle. Sealing the inside edge with a formed in place RTV seal initially worked but it too has been overcome. Something more effective on the inside is needed to prevent entry.

Front of right main landing gear wheel fairing to subfairing:
IMG_6142.jpg

This looks like an air impact failure across the overlap seam. Never had such a failure with cloth reinforced gaffer's tape.

Upper end of left main landing gear strut:
IMG_6135.jpg

This appears to be a failure where a vacuum aft of the thickest part of the cuff and strut fairing lifted the tape from the lower edge and ripped it off.

My conclusions:

On the long flat side surfaces of the wheel fairings to subfairings the 3M 471 appears to work well but not the front. It also appears to have insufficient strength to stand up to 180+ kt air impact against leading edges where the tape covers an edge on lap joint even though it is carefully formed to conform to the surfaces on both sides of the joint.

The adhesive on the tape is not strong enough to maintain attachment under internal pressure or external vacuum conditions.

The black color was acceptable for a race from an appearance perspective - that is important to me.

At this point my thoughts in preparation for the AirVenture Cup race a week and a half from now are to consider a hybrid application of Gaffer's tape on impact points, 3M 471 in the low stress sides and better internal seals of the cuffs.

Bob Axsom
 
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Progressive observation

That prihibitively expensive 3M 471 black tape I bought ($50/roll) has some good applications on sides where there is no internal pressure. It lays on very smooth and seems to stay in place. Some preliminary tests with 3M 471 applied first then overlayed on the leading edge with gaffer's tape seems to hold up fairly well. This appears to be one of those artsie science things that requires some special techniques to make it work.

Bob Axsom
 
Hey Bob


We have been using that tape to cover some things not painted yet, lucky for me it matches my paint almost exactly. Anyway, I have not any issues with the tape peeling or tearing. Have it on the wing intersection fairing, the upper gear leg fairing, as rudder cable fairings, and on the front of the cowl (it wraps around from the front face to the side to cover my shiny hinge cover plates).

Have been to 181 knots twice without issue. That is without complete full power and wheel pants. I sure hope that reading is correct. :)
 
WOW! You've got a racer there

181 KTS without fairings is awesome Wade - those 8s are super fast. You should enter one of the races in Texas this year:

Galvaston 6 Oct
Cleveland 13 Oct
Jasper 27 Oct
Taylor 10 Nov

Check the details under Calendar of Events at www.sportairrace.org

Bob Axsom
 
Thanks Bob. I am shooting for Taylor but don't know if I will get all of the flight test completed by then.

Even if I don't race, it is within my test area so I will at least be there to soak it all in.
 
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